The distinction between two models of reliability is clarified. Reliability may be conceived of and estimated from a true score model or from the perspective of sampling precision. Basic models are developed and illustrated for each approach using data from the author's work on measuring organizational climate. (SLD)

Describes a one-week lesson in which gummy-bears candy was used to illustrate sampling procedures and to generate discussion and questions. Reports data results and students' reactions to problems of representation after holding an election. (MKR)

An exploratory study of 192 homeless shelters in 29 cities used structural equation analysis to analyze characteristics of organizational and service delivery systems. The resulting model showed that services offered by the shelters are best understood as being influenced by organizational structure mediated through the organization's relationship…

Equating a new standard test to an old reference test is considered when samples for equating are not randomly selected from the target population of test takers, identifying two problems from equating from biased samples. An empirical example with data from the Armed Services Vocational Aptitude Battery illustrates the approach. (SLD)

This response to an article on recommended practices in early intervention/early childhood special education identified by the Council for Exceptional Children's Division for Early Childhood raises concerns about the characteristics of the validation sample, the discrepancy between acceptance and use of recommended practices, and implications for…

This commentary on EC 603 695 argues that significance testing is a necessary but insufficient condition for positivistic research, that judgment-based assessment and single-subject research are not substitutes for significance testing, and that sampling fluctuation should be considered as one of numerous epistemological concerns in any…

The article by W. K. Estes marks a turning point in the mathematical learning theory movement. The central constructs were stimulus variability, stimulus sampling, and stimulus response association by contiguity, in a framework enabling prediction of response probability and latency. (SLD)

This study comparing momentary time sampling against the real time obtained with handheld computers confirmed laboratory findings that short-elementary time sampling estimates percentage time accurately for a wide range of behavior frequencies and durations, and suggested that observers using momentary time sampling in a natural setting are able…

Studied the small sample behavior of several test statistics based on the maximum-likelihood estimator but designed to perform better with nonnormal data. Monte Carlo results indicate the satisfactory performance of the "F" statistic recently proposed by K. Yuan and P. Bentler (1997). (SLD)

Presents an activity on the simplification of penguin counting by employing the basic ideas and principles of sampling to teach students to understand and recognize its role in statistical claims. Emphasizes estimation, data analysis and interpretation, and central limit theorem. Includes a list of items for classroom discussion. (ASK)

The effect of removing nonfunctioning items from multiple-choice tests was studied by examining change in difficulty, discrimination, and dimensionality. Results provide additional support for the benefits of eliminating nonfunctioning options, such as enhanced score reliability, reduced testing time, potential for broader domain sampling, and…

This activity makes students a part of an investigation that determines the frequency of a particular plant variety in a simulated population. Provides an opportunity for students to observe the inherent variability of estimates, observe the relationship between sample size and sampling error, and consider aspects of research design. (Author/SAH)

Demonstrates that by using barcodes to identify random lists of books, taking small monthly samples, and updating a simple control chart, one can effectively: (1) pinpoint reasons why library books are unavailable; (2) gauge if corrective actions or changes in procedure are needed; and (3) determine if such actions are successful. Contains two…

Discusses the extent to which the existing literature offers insights into effectively teaching statistical inference. Describes an in-class exercise that helps students understand inferential statistics. Explains that students learn more about concepts such as population distribution, sampling distributions, and standard error of the estimate.…

Objective: The 1998 Canadian Incidence Study of Reported Child Abuse and Neglect (CIS-98) is the first national study to document the rate of intentionally false allegations of abuse and neglect investigated by child welfare services in Canada. This paper provides a detailed summary of the characteristics associated with intentionally false…